You know what will add even more stress to your already stressful work life? Not having an active life running on all cylinders outside of work.

People who balance the emotional and physical pounding of 50 to 60 hours a week on the job with personal interests, hobbies, and self-care are typically more productive and emotionally engaged in their work. They also hardly ever burn out.

Simply put: An active and successful personal life begets success in your work life.

If you find that you're teetering dangerously close to being out of balance, consider how the world's most famous billionaires manage to decompress with their own outside activities.

Warren Buffett

The billionaire investor and CEO of Berkshire Hathaway balances his life by playing two things: bridge and his famous ukulele (including on live television). His love for the tiny four-stringed guitar spans decades, going back to the day he learned it in college to impress a young woman. He even uses this hobby for charitable giving, auctioning off an autographed ukulele on eBay and donating the proceeds to Omaha's Children's Hospital. Even science will tell you that the brain benefits greatly from playing an instrument.

Richard Branson

The Virgin billionaire is known for his many wild adventures and having an array of interests and hobbies. One that stands out is his favorite sport of kitesurfing, in which, with favorable wind conditions, you may find him shredding surf around his famous Necker Island, occasionally with a naked model on his back.

Oprah Winfrey

Oprah Winfrey practices Transcendental Meditation. She sits in stillness for 20 minutes twice a day. She says, "Only from that space can you create your best work and your best life." Setting aside this little ritual every day during your spare time will make the rest of your week seem manageable. You'll notice a difference and that a weight has come off your shoulders. It works for Oprah.

Mark Cuban

One cannot forget the priority of putting family first. The billionaire investor and Shark Tank co-host is no exception. He makes sure he's available for his loved ones, stressing the importance of marriage and a home life. Cuban told a South by Southwest audience:

On the weekends we have [a nanny] in the morning, so Tiff and I go work out Saturday mornings. Then the rest of the weekend it's just us. It's us putting them to bed. It's us at dinner. We try to be as normal as possible.

Daymond John

The CEO of Fubu and investor on Shark Tank takes the edge off by spending weekends at his lakeside cabin in Dutchess County, New York, catching largemouth bass. He tells The New York Times, "I'll wake up at 5:30, because the fish don't wait for anybody. Hopefully, I'll usually catch maybe 15 largemouth bass. That's a great day." John also raises guinea hens -- about 150 of them -- for fresh eggs. He's a huge fan of photography and enjoys reading and writing books.

Simon Cowell

The X Factor judge and former American Idol judge's hobbies have a boyish charm. He once told Entertainment Tonight, "I climb trees, daily." He also told GQ magazine he watches cartoons each morning, like The Flintstones and The Jetsons. He says, "It's less depressing than watching the news."

Bringing It Home

The key to success at work starts with managing your life outside of work. And you do that by maintaining an active and well-balanced life as you climb the ladder of success. It'll help keep your sanity and protect you from anxiety, stress, and burnout.